Indoor air conditioner

Abstract

This indoor air conditioner comprises: a casing that has an inlet and an air outlet; a cross-flow fan that is provided in the casing, and that by being rotationally driven about an axis which extends horizontally takes in air through the inlet and blows air toward the air outlet; a heat exchanger that is provided in the casing and that is provided so as to surround the axis of the cross-flow fan from the outer peripheral side; and a leakage-detecting sensor that is provided below the heat exchanger inside the casing, wherein the leakage-detecting sensor is provided at a position differing from that of an air path through which airflow from the cross-flow fan flows.

Description

Indoor air conditioner

[0001] This application claims priority to Japanese Patent Application No. 2023-142178, filed September 1, 2023, the contents of which are incorporated herein by reference.

[0002] A known technology for detecting refrigerant leakage in an air conditioner is described in Patent Document 1. In the device described in Patent Document 1, a sensor for detecting refrigerant leakage is disposed on a path (air duct) through which air passes from an indoor unit (indoor air conditioner). This is said to enable detection of refrigerant leakage from a heat exchanger.

[0003] International Publication No. 2020 / 179007

[0004] However, when a leak detection sensor is placed on the air duct as described above, while leaks can be detected while the indoor air conditioner is operating, there is a problem in that it is difficult to detect leaks when the air conditioner is stopped because no air passes through the air duct.

[0005] The present disclosure provides an indoor air conditioner that is capable of detecting refrigerant leakage with high accuracy regardless of the operating state.

[0006] The indoor air conditioner of the present disclosure comprises a casing having an intake port and an exhaust port, a crossflow fan provided within the casing and driven to rotate about an axis extending horizontally, thereby drawing in air through the intake port and blowing the air towards the exhaust port, a heat exchanger provided within the casing so as to surround the crossflow fan from the outer periphery of the axis, and a leak detection sensor provided below the heat exchanger within the casing, wherein the leak detection sensor is provided at a position different from the air path through which the air blown by the crossflow fan flows.

[0007] According to the present disclosure, it is possible to provide an indoor air conditioner that is capable of detecting refrigerant leakage with high accuracy regardless of the operating state.

[0008] Fig. 1 is a cross-sectional view showing a configuration of an indoor air conditioner according to an embodiment of the present disclosure; Fig. 2 is an enlarged front view of a main part of the indoor air conditioner according to an embodiment of the present disclosure; Fig. 3 is a cross-sectional view showing a first modified example of the indoor air conditioner according to an embodiment of the present disclosure; Fig. 4 is a cross-sectional view showing a second modified example of the indoor air conditioner according to an embodiment of the present disclosure.

[0009] (Configuration of Indoor Air Conditioner) An indoor air conditioner 1 according to an embodiment of the present disclosure will be described below with reference to Figs. 1 and 2. The indoor air conditioner 1 is an air conditioning device that is attached to an indoor wall surface for use. It has a refrigeration cycle that circulates a refrigerant between an indoor unit (not shown) and an outdoor unit. Temperature-regulated air is supplied to the room through heat exchange between the indoor air and the refrigerant, and between the outdoor air and the refrigerant.

[0010] As shown in FIG. 1 , the indoor air conditioner 1 includes a casing 10, a crossflow fan 20, a heat exchanger 30, a drain pan 40, an inner cover 50, an air path forming plate 60, and a leak detection sensor 70.

[0011] (Casing Configuration) The casing 10 is a decorative cover that forms the exterior of the air conditioner, and has a front cover 11 facing the front on the indoor side, a top cover 12 facing the top, a bottom cover 13 facing the bottom, a back cover 14 facing the back side (i.e., the wall side), and side covers (not shown). The top cover 12 is formed with an intake port 15 for drawing indoor air into the device.

[0012] The bottom cover 13 has a cover body 16 and a flap 17. The cover body 16 is fixed to the rear panel. Meanwhile, the flap 17 is supported so as to be able to swing relative to the cover body 16. The swing axis of the flap 17 extends horizontally. When the flap 17 swings, an opening is formed in a part of the bottom cover 13. This opening serves as an air outlet 18 for blowing out temperature-regulated air inside the device. In other words, by changing the swing angle of the flap 17, the direction of air blown from the air outlet 18 can be adjusted.

[0013] (Configuration of the crossflow fan) The crossflow fan 20 is a cylindrical fan centered on an axis X extending horizontally, and is driven to rotate about this axis X. As the crossflow fan 20 rotates, indoor air is drawn into the device through the air inlet 15. In addition to the crossflow fan 20, a sirocco fan can also be used for the same purpose. A drive unit (not shown) for the crossflow fan 20 is provided at one end or the other end in the direction of the axis X. The crossflow fan 20 is also located in the center of the casing 10 when viewed from the direction of the axis X.

[0014] (Configuration of Heat Exchanger) The heat exchanger 30 covers the outer periphery of the crossflow fan 20 in the direction of the axis X. The heat exchanger 30 is, for example, a fin-and-tube type and is filled with a refrigerant. The refrigerant exchanges heat with the indoor air, thereby adjusting the temperature of the air being blown. As an example, the heat exchanger 30 is divided into three blocks: a rear block 31 located on the rear side; an upper front block 32 located on the front side adjacent to the rear block 31; and a lower front block 33 located below the upper front block 32. The refrigerant flow paths between all of the blocks are interconnected. From the perspective of reducing environmental impact, a propane-based refrigerant such as R290 is particularly preferred.

[0015] (Configuration of Drain Pan) A drain pan 40 is provided below the lower front block 33. The drain pan 40 is a member for receiving condensation water generated on the surface of the heat exchanger 30. The drain pan 40 has a drain pan body 41 and a receiving tray 42. The drain pan body 41 is U-shaped when viewed from the direction of the axis X so as to cover the lower part of the lower front block 33. Condensation water that drips onto the drain pan body 41 is discharged to the outside of the room through piping (not shown).

[0016] A receptacle portion 42 is integrally provided on the front side of the drain pan body 41. The receptacle portion 42 has an L-shaped cross section that protrudes from the front side of the drain pan body 41. The receptacle portion 42 is provided to form a space (a detection space V) that is different from the airflow path F described below. As shown in FIG. 2 , the receptacle portion 42 slopes downward toward the center in the direction of the axis X when viewed from the front side.

[0017] (Configuration of the Inner Cover) An inner cover 50 is provided between the heat exchanger 30 and the casing 10. The inner cover 50 covers the heat exchanger 30 from the outer periphery with respect to the axis X. A filter (not shown) and the like are detachably attached to the inner cover 50. The lower end of the front side of the inner cover 50, together with the above-mentioned tray portion 42 and a portion of the drain pan body 41, forms an internal space. This space is defined as a detection space V. A leak detection sensor 70 is provided in the center of this detection space V in the direction of the axis X. The leak detection sensor 70 is an element for detecting refrigerant leakage from the heat exchanger 30. As an example, the leak detection sensor 70 is fixed to the front surface of the drain pan body 41 via a stay 71. Furthermore, considering the flow of refrigerant due to its own weight, it is desirable that the refrigerant detection sensor be positioned further below the lower end of the heat exchanger 30.

[0018] (Configuration of Air-Path Forming Plate) An air-path forming plate 60 is provided on the rear side of the heat exchanger 30 and the cross-flow fan 20. The air-path forming plate 60 has a forming plate main body 61 and a curved portion 62. The forming plate main body 61 is provided on the rear side of the rear block 31 of the heat exchanger 30. The forming plate main body 61 extends in the vertical direction. A portion of the forming plate main body 61 protrudes toward the rear cover 14. A curved portion 62 is integrally connected to the lower end of the forming plate main body 61. The curved portion 62 covers the cross-flow fan 20 and extends downward to the edge of the air outlet 18. The curved portion 62 is curved in an arc shape that convexly faces the rear side to match the cylindrical shape of the cross-flow fan 20. The front surface of the curved portion 62 (i.e., the surface facing the cross-flow fan 20) is a cylindrical inner circumferential surface 63.

[0019] The space surrounded by the drain pan 40, the inner cover 50, and the air-path forming plate 60 serves as an air path F through which the air compressed by the cross flow fan 20 flows. In other words, the detection space V is a separate space independent of the air path F, and no air flows into the detection space V, whether the fan is operating or not.

[0020] (Operation and Effect) To operate the indoor air conditioner 1, first, the power is turned on to rotate the cross flow fan 20. At the same time, the refrigerant flowing in from the outdoor unit flows into the heat exchanger 30. The temperature of the air sent to the periphery of the heat exchanger 30 by the cross flow fan 20 is adjusted by heat exchange with the refrigerant. The temperature-adjusted air is then pressure-fed by the cross flow fan 20 through the air outlet 18 into the room.

[0021] Here, it is possible that the refrigerant in the heat exchanger 30 may leak. Refrigerant leakage affects the operation of the indoor air conditioner 1, so it is desirable to detect it immediately. For this reason, a conventional example has been proposed in which the leak detection sensor 70 is disposed on the air duct F for blowing air. However, when the leak detection sensor 70 is disposed on the air duct F, while it is possible to detect a leak while the indoor air conditioner 1 is operating, blown air does not pass through the air duct F when the indoor air conditioner 1 is stopped, which makes it difficult to detect a leak or requires a long time to detect a leak. Therefore, the present embodiment employs the above-described configurations.

[0022] According to the above configuration, since the leak detection sensor 70 is provided at a position different from the air duct F (i.e., in the detection space V), refrigerant leakage can be detected even when no air is flowing through the air duct F, i.e., when the indoor air conditioner 1 is stopped. In particular, since refrigerant leaking from the heat exchanger 30 has a higher specific gravity than air, it passes through gaps between the heat exchanger 30 and the inner cover 50 and reaches the detection space V. For this reason, refrigerant leakage can be immediately detected even when the indoor air conditioner 1 is stopped. This makes it possible to further increase the availability of the indoor air conditioner 1.

[0023] It is known that leakage is particularly likely to occur at the curved portions 62 of the heat transfer tubes at both ends in the axial direction of the heat exchanger 30. Refrigerant leaking from these locations passes along the sides of the heat exchanger 30 and reaches the tray portion 42 due to its own weight. It then diffuses along the axial direction of the heat exchanger 30 and reaches the center of the tray portion 42. According to the above configuration, since the leakage detection sensor 70 is provided in the center of the tray portion 42, leakage from either side in the axial direction of the heat exchanger 30 can be immediately detected. This allows for stable operation of the indoor air conditioner 1.

[0024] According to the above configuration, the surface of the tray 42 facing the drain pan body 41 slopes downward toward the center, which makes it easier for the refrigerant to be guided toward the center by its own weight toward the leak detection sensor 70. In other words, the refrigerant flows downward along the downward slope and accumulates in the center. Therefore, even a very small leak can be detected immediately and with high accuracy by the leak detection sensor 70.

[0025] According to the above configuration, by providing only one leak detection sensor 70 in the center, it is possible to detect leaks at any location in the heat exchanger 30. This minimizes the number of leak detection sensors 70, which were previously provided in multiple locations, and therefore reduces manufacturing and maintenance costs.

[0026] (Other Embodiments) Although the embodiments of the present disclosure have been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like within the scope that does not deviate from the gist of the present disclosure are also included.

[0027] For example, in the above embodiment, an example has been described in which the leak detection sensor 70 is disposed in the detection space V. However, it is also possible to dispose the leak detection sensor 70 in a location other than the detection space V, as long as it is in a position different from the air passage F. Specifically, as shown as a first modified example in FIG. 3 , it is possible to dispose the leak detection sensor 70 in the space on the rear side formed by the curved portion 62 of the air passage forming plate 60 and the rear cover 14. Even in this case, the same effects as those described above can be obtained.

[0028] It is also possible to place one leak detection sensor 70 in each of the detection space V and the back space (FIG. 4). In this case, refrigerant leaks can be detected more precisely and immediately.

[0029] It is also possible to arrange two or more leak detection sensors 70 at intervals in each of the detection space V and the back space. In this case, it is also possible to detect refrigerant leaks more precisely and immediately.

[0030] Furthermore, in the above embodiment, an example has been described in which the leak detection sensor 70 is provided in the center of the detection space V (the tray portion 42) in the direction of the axis X. However, the leak detection sensor 70 may also be disposed at an end of the tray portion 42 in the direction of the axis X. This configuration makes it easier to route the wiring compared to when the sensor is provided in the center of the tray portion 42. This allows for improved workability during manufacturing and maintenance.

[0031] The shape and block configuration of the heat exchanger 30 described above are merely examples, and can be modified as appropriate depending on the design and specifications. Similarly, the positions and dimensions of the air inlet 15 and the air outlet 18 can also be modified as appropriate depending on the design and specifications. In any case, the same effects as those described above can be obtained.

[0032] In the above embodiment, an example has been described in which the leak detection sensor 70 is supported by the stay 71. However, the manner in which the leak detection sensor 70 is fixed is not limited to this, and as another example, the leak detection sensor 70 can be attached and fixed to the target surface using double-sided tape or the like.

[0033] <Additional Notes> The indoor air conditioner 1 described in each embodiment can be understood, for example, as follows.

[0034] (1) The indoor air conditioner 1 according to the first aspect includes a casing 10 having an intake port 15 and an exhaust port 18, a cross-flow fan 20 provided within the casing 10 and driven to rotate about an axis X extending horizontally, thereby drawing in air through the intake port 15 and blowing the air toward the exhaust port 18, a heat exchanger 30 provided within the casing 10 so as to surround the cross-flow fan 20 from the outer periphery of the axis X, and a leak detection sensor 70 provided below the heat exchanger 30 within the casing 10, wherein the leak detection sensor 70 is provided at a position different from an air duct F through which the air blown by the cross-flow fan 20 flows.

[0035] According to the above configuration, since the leak detection sensor 70 is provided at a position different from the air duct F, refrigerant leakage can be detected even when no air is flowing through the air duct F, i.e., when the indoor air conditioner 1 is stopped.

[0036] (2) The indoor air conditioner 1 according to a second aspect is the indoor air conditioner 1 of (1), further comprising a drain pan 40 that covers the heat exchanger 30 from below, the drain pan 40 having a drain pan main body 41 facing the heat exchanger 30, and a receptacle portion 42 that is provided further below the drain pan main body 41 and forms a detection space V extending in the direction of the axis X between the receptacle portion 42 and the drain pan main body 41, and the leakage detection sensor 70 is provided in the center of the receptacle portion 42 in the direction of the axis X.

[0037] It is known that in the heat exchanger 30, leakage is particularly likely to occur at the curved portions 62 of the heat transfer tubes at both ends in the direction of the axis X. Refrigerant leaking from these locations passes along the sides of the heat exchanger 30 and reaches the tray portion 42 due to its own weight. The refrigerant then diffuses in the direction of the axis X and reaches the center of the tray portion 42. According to the above configuration, since the leakage detection sensor 70 is provided in the center of the tray portion 42, leakage from either side in the direction of the axis X can be immediately detected.

[0038] (3) The indoor air conditioner 1 according to a third aspect is the indoor air conditioner 1 of (2), further comprising a drain pan 40 that covers the heat exchanger 30 from below, the drain pan 40 having a drain pan main body 41 facing the heat exchanger 30, and a receptacle portion 42 that is provided further below the drain pan main body 41 and forms a detection space V extending in the direction of the axis X between the receptacle portion 42 and the drain pan main body 41, and the leakage detection sensor 70 is provided at an end of the receptacle portion 42 in the direction of the axis X.

[0039] According to the above configuration, the leak detection sensor 70 is provided at the end of the tray 42, which makes it easier to route the wiring compared to when the sensor is provided in the center of the tray 42. This makes it possible to improve workability during manufacturing and maintenance.

[0040] (4) The indoor air conditioner 1 according to the fourth aspect is the indoor air conditioner 1 according to (2), in which the surface of the tray portion 42 facing the drain pan main body 41 is inclined downwardly as it approaches the center in the direction of the axis X.

[0041] According to the above configuration, the surface of the tray 42 facing the drain pan body 41 slopes downward toward the center, which makes it easier for the refrigerant to be guided toward the center by its own weight toward the leak detection sensor 70. Therefore, even if there is a very small amount of leakage, the leak detection sensor 70 can detect it immediately and with high accuracy.

[0042] (5) The indoor air conditioner 1 according to the fifth aspect is the indoor air conditioner 1 according to any one of aspects (2) to (4), in which only one leak detection sensor 70 is provided within the detection space V.

[0043] According to the above configuration, by providing only one leak detection sensor 70 in the center, it is possible to detect leaks at any location in the heat exchanger 30. This minimizes the number of leak detection sensors 70, which were previously provided in multiple locations, and therefore reduces manufacturing and maintenance costs.

[0044] (6) The indoor air conditioner 1 according to the sixth aspect is the indoor air conditioner 1 of (1), and further includes an air path forming plate 60 having a cylindrical inner surface 63 that covers the heat exchanger 30 from the opposite side of the intake port 15 across the heat exchanger 30, thereby forming the air path F that communicates with the air outlet 18, and the leakage detection sensor 70 is positioned in the center in the direction of the axis X of the second detection space V formed by the air path forming plate 60 and the rear panel.

[0045] According to the above configuration, since the leak detection sensor 70 is provided outside the air-path forming plate 60, i.e., between the air-path forming plate 60 and the rear panel, it is possible to detect refrigerant leakage even when no air is flowing through the air path F, i.e., when the indoor air conditioner 1 is stopped. In addition, according to the above configuration, since the leak detection sensor 70 is provided in the center of the tray portion 42, it is possible to immediately detect leakage from either side of the heat exchanger 30 in the direction of the axis X.

[0046] (7) The indoor air conditioner 1 according to a seventh aspect is the indoor air conditioner 1 according to (6), in which only one leakage detection sensor 70 is provided in the second detection space V.

[0047] According to the above configuration, by providing only one leak detection sensor 70 in the center, it is possible to detect leaks at any location in the heat exchanger 30. This minimizes the number of leak detection sensors 70, which were previously provided in multiple locations, and therefore reduces manufacturing and maintenance costs.

[0048] According to the present disclosure, it is possible to provide an indoor air conditioner that is capable of detecting refrigerant leakage with high accuracy regardless of the operating state.

[0049] DESCRIPTION OF SYMBOLS 1...Indoor air conditioner 10...Casing 11...Front cover 12...Top cover 13...Bottom cover 14...Rear cover 15...Intake port 16...Cover body 17...Flap 18...Air outlet 20...Cross flow fan 30...Heat exchanger 31...Rear block 32...Upper front block 33...Lower front block 40...Drain pan 41...Drain pan body 42...Receptacle portion 50...Inner cover 60...Air path forming plate 61...Forming plate body 62...Curved portion 63...Cylinder inner surface 70...Leak detection sensor 71...Stay F...Air path V...Detection space X...Axis

Claims

1. An indoor air conditioner comprising: a casing having an intake port and an exhaust port; a crossflow fan provided within the casing and driven to rotate about an axis extending horizontally, thereby drawing in air through the intake port and blowing the air towards the exhaust port; a heat exchanger provided within the casing so as to surround the crossflow fan from the outer periphery of the axis; and a leak detection sensor provided below the heat exchanger within the casing, wherein the leak detection sensor is provided in a position different from the air path through which the air blown by the crossflow fan flows.

2. An indoor air conditioner as described in claim 1, further comprising a drain pan covering the heat exchanger from below, the drain pan having a drain pan body facing the heat exchanger, and a receptacle portion provided further below the drain pan body and forming a detection space extending in the axial direction between the receptacle portion and the drain pan body, the leakage detection sensor being provided in the center of the axial direction of the receptacle portion.

3. An indoor air conditioner as described in claim 1, further comprising a drain pan covering the heat exchanger from below, the drain pan having a drain pan body facing the heat exchanger, and a receptacle portion provided further below the drain pan body and forming a detection space extending in the axial direction between the receptacle portion and the drain pan body, the leak detection sensor being provided at an end of the receptacle portion in the axial direction.

4. An indoor air conditioner as set forth in claim 2, wherein the surface of said tray portion facing said drain pan body is inclined downwardly toward the center in the axial direction.

5. An indoor air conditioner according to any one of claims 2 to 4, wherein only one leakage detection sensor is provided within the detection space.

6. An indoor air conditioner as described in claim 1, further comprising an air path forming plate having a cylindrical inner circumferential surface that covers the heat exchanger from the side opposite the intake port, thereby forming the air path communicating with the air outlet, wherein the leakage detection sensor is disposed in the center in the axial direction of a second detection space formed by the air path forming plate and the rear panel.

7. The indoor air conditioner according to claim 6, wherein only one leakage detection sensor is provided in the second detection space.

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